Dark Energy or Modified Gravity?

Different gravity models are degenerate when looking at the expansion history of the Universe H(z) only. Such degen
eracy, can be lifted if we focus on the gravity­‐driven growth of cosmological structures, measuring the growth rate f(z). “Redshiſt-­‐Space Distortions” (RSDs), quantified through the two-­point correlation function (2PCF) are a potentially powerful way to extract this information. Yet, separating the linear RSD signal, which depends on f(z), from nonlinear distortions is complicated. This can be achieved either through improved modelling, or by choosing specific statistics or tracers of large scale structure that are less sensitive to the non-­linear contributions. Here we present the results one obtains when using the group-­galaxy cross correlation as an alternative to the traditional auto-­correlation function.

Click here to view the full poster presented by Faizan Mohammad in Tallinn at the Zeldovich Universe

Here below you can download also the other posters and presentations prepared by the team:

Measuring the growth rate of structure around cosmic voids in VIPERS by Adam Hawken

Improving the correction of angular selection effects in VIPERS clustering measurements by Andrea Pezzotta

Improving the modelling of redshit-space distortions: a bivariate gaussian description for the galaxy pairwise velocity distributions by Davide Bianchi

Measuring the VIPERS galaxy power spectrum at z~1 by Stefano Rota